David Reimer, a Winnipeg man born a boy but raised a girl after a botched circumcision, took his own life last week. He was 38.

Reimer, who was baptized Bruce, was raised until the age of 14 as a girl named Brenda on the advice of a sex researcher at Johns Hopkins Hospital.

Dr. John Money believed that gender identity was determined more by nurture than nature, and he took Reimer's botched circumcision as an opportunity to try to prove his theory in an experiment known as the John/Joan case in the 1960s and '70s.

Money advised Reimer's parents to give their son female hormones and raise him as a girl. His development was followed closely, and compared to his identical twin brother, Brian, who was raised as a boy.

Reimer struggled with his identity into his teens. He was teased for his gunslinger stride and lack of interest in boys. Doctors told her the discomfort was due to passing "tomboyishness."

When finally told the truth at the age of 14, Reimer rebelled and resumed his male identity. He changed his name to David, eventually married and became a stepfather to three children.

His story was told by author John Colapinto, who wrote As Nature Made Him: The Boy Who Was Raised as a Girl. Reimer said it was important to raise the troubling issue of sexual reassignment -- a topic he brought to the Oprah Winfrey show.

His mother, Janet, said he had recently become depressed after losing his job and separating from his wife. She said he was also still grieving the death of his brother two years earlier.

"He managed to have so much courage," Ms. Reimer said yesterday. "I think he felt he had no options. It just kept building up and building up."

She blames the gender study for her son's death.